Evaporator



July 11, 1933. F SLAGEL 1,917,667

EvAPoRAToR Filed April 17, 1930 Patented July 1l, 1933 UNITED STATES PATENT OFFICE FRANKLIN G. SLAGEL, OF BUFFALO, ANEW YORK, ASSIGNOR TO FEDDERS MANUFACTUR- ING COMPANY, INC., OF BUFFALO, NEW YORK, A CORPORATION F NEW YORK EVAPORATOR Appiieation med p1-niv, 1930. 'semi ini.A` (145,119.

This invention relates to mechanical refrigerating systems, and more particularly to evaporators.

An object of the invention is to provide an 5 evaporator of the flooded type which is 0 relative proportion as admitted to the evaporator.

Another object of the invention is to provide an evaporator with an auxiliary chamber arranged in communication with the vapor space in a liquid refrigerant container to increase thegas capacity, such structure being especially adapted for commercial uses.

Other objects of the invention will appear from the following description taken in con- 9 nec-tion with the drawing, which forms a part of the specification, and in which:

Fig. 1 is an end elevation of an evaporator, and Fig. 2 is a medial vertical sectional view taken on line 2 24 of Fig. 1.

A cylindrically shaped container, or vessel. 10 forms a reservoir in which a substantially constant quantity of liquid refrigerant iS automatically maintained. Closing one end of the container is a plate 11 which has a passage 12 therethrough for admitting the liquid refrigerant into the container, such passage communicating with a union 13 to which the conduit 14, leading from the condenser (not shown), is secured. In order to 5 maintain the body of liquid refrigerant in the container, I provide a float 15 which is pivotally mounted on the pin 16 carried by a support 17. The ioat arm is pivotally connected to a needle valve 18 which opens and l closes the passage in the valve seat 19 extending into the passage 12. The float is calibrated to move with the liquid level and thereby open the valve as the liquid refrigerant in the container evaporates and to move the valve to closed position when the liquid reaches a predetermined high level.

In order that refrigerant returning to the compressor (not shown) is completely gasiied before entering the return conduits 20, I provide an auxiliary chamber 21 which communicates with the vapor space in the container, but in a zone remote therefrom. Such chamber is in the form of a cylindrical vessel arranged preferably in a plane above the container and of a relatively smaller capacity. A plurality of tubes or duct means 22 are arranged between the chamber and the container establishing open communication between the vapor space in the container and the chamber.

In order to increase the heat transfer capacity of the evaporator, I provide duct means extending laterally from the container and communicating with vthe chamber. Such duct means include a plurality of laterally extending tubes 23 communicating at one end with the container, in diferent planes below the liquid level. The ends of the tubes 23, remote from the container, are joined by a common tube 24 which is connected with the tube 25 leading into the chamber. The tubes 23 and the lower portion of the tubes 24 are filled with liquid refrigerant ilowing from the container, while the upper portion of the tube 24 and the tube 25 provide a return for refrigerant gasifying in the other portion of the duct means.

It will be seen that absorbing of heat by the liquid refrigerant causes violent boiling such that gas rising from the liquid in the container and in the duct means will carry free liquid particles therewith. By causing the liquid particles to pass into the chamber, the time consumed in such travel and the heat of the chamber will either gasify the particles or they will drain back into the body of liquid in the container. In this manner gasified refrigerant drawn from the chamber will be completely free of wet refrigerant.

The chamber is provided with end walls 26 through'which the return conduits 20, leading to the compressor, extend. l Such conduits project into the chamber with their open ends intermediate the tubes E22, thus placing the open ends out of the path of any liquid particles passing into the chamber. In order to further increase the heat transfer capacity of the evaporator, above described, suitable fins 27 are arranged in intimate contact with the laterally extending duct means.

When the evaporator is of the type in which lubricating oil travels in cycle through a compressor-condonser-evaporator system with the refrigerant absorbing only a limited amount of the oil, then I provide means for shunting the oil liberating and rising to the liquid body surface when refrigerant evaporates directly to one of the outlets leading from the chamber. Assuming that oil and sulphur dioxide are used as the liquid traveling in solution in the system, then the gasification of liquid refrigerant in the container will liberate the quantity of oil in solution therewith..7 and such free oil rises to the top of the liquid solution body.

A tube 30 depends into the container With an open end arranged in a position so that it is just level with the highest surface of the liquid body in solution. Such tube eX- tends into an outlet passage 3l in the end plate and a coupling 39. connects the passage 81 with a conduit leading to one of the gas outlet conduits 20. The compressor suction will draw oil through the tubes 30 and 33 as it rises to the top of the body in solution in the container, thus preventing the forma-r tion of an oil blanket which would impede the release of gasified refrigerant in rising from the body in solution.

- It will be seen that the refrigerant and oil will be automatically maintained in the same relation of quantities in the container. The gasiied refrigerant passing into the outlet suction tubes will be dry` and the gas space in the evaporator is sufficient to care for a quantity rising from a commercial type of structure which includes an exterior duct means and fins and which holds a large quantity of liquid refrigerant.

Although this invention has been described in connection with certain specific embodiments, the principles involved are susceptible of numerous other applications which will readily occur to persons skilled in the art, and the invention is therefore to be limited only as indicated by the scope of the appended claims.

What I claim is:

1. In an evaporator for refrigerating systems` a container, means for maintaining the container partially filled with a body of liquid refrigerant, a chamber in a plane above the body of refrigerant in the container, tubes establishing communication between the vapor space in the container and the chamber, and a pair of outlet conduits leading from the chamber, the open ends -of outlet tubes extending inwardly of the chamber to zones intermediate the tubes leading from the container.

2. In a refrigerating system which includes a compressor and a condenser, an evaporator comprising a container, means for maintaining the container filled partially with liquid refrigerant and oil solution, a chamber connected with the vapor space in the container, an outlet leading from the chamber, and a tube extending into the container with an open end in a plane with the high level of the liquid to conduct oil from the container, the other end of the tube being in open communication with the outlet leading from the chamber.

8. In an evaporator for refrigerating systems', a container, means for maintaining a substantially constant body of liquid refrigerant 'in the container, a super-posed chamber in open communication with the container, an outlet conduit leading from the chamber, and separate duct means in open communication with the liquid refrigerant in the container and with the outlet conduit leading from the chamber.

4. In an evaporator for refrigerating systems, a container, means for maintaining a body of liquid refrigerant in the container, a chamber above the container, a plurality of laterally extending tubes having one end communicating with the container below the liquid level therein and communicating with the chamber, and tube means establishing a connection between the chamber and the first mentioned tubes, and a gas outlet leading from the chamber.

5. In an evaporator for refrigerating systems, a container, means for maintaining a body of liquid refrigerant in the container, a chamber above the container, a plurality of laterally extending tubes in a parallel relation and connected at one end to the container in a plane below the liquid level, a connection between the tubes and the chamber, and an outlet from the chamber.

6. In an evaporator for refrigerating systems, a container, means for admitting liquid refrigerant and oil of different specific gravities into the container to maintain a substantially constant body of liquid therein, a super-posed chamber in open communication with the container, a refrigerant gas outlet conduit leading from the chamber, and an oil outlet conduit leading from the container and communicating with the gas conduit eX- teriorly of the chamber, said oil conduit having an end open to oil accumulating Iin the container.

7. An evaporator for a refrigerating system comprising a container adapted to receive liquid refrigerant admiXed with oil, a float controlled valve in the container for conreturn line having its opposite end in communication with one of said return conduits, the diameter of said oil line being relatively small compared to its length, whereby iow of gasiied refrigerant throu-gh said return conduits will induce the flow of supernatant oil adjacent the inner end of the oil line.

In testimony whereof I aflx my signature.

FRANKLIN G. SLAGEL. 

